Disposable plastic bottles of liquid such as water, soda and the like have relatively small necks which are sealed with a removable cover prior to use. Users, once the cover is removed and the neck is open, can drink from the open neck. However, when the user is walking or running, it is difficult for the user to drink from a tilted bottle. In addition, while the user can hold the bottle in one hand for drinking, in order to prevent the bottle from leaking prior to reuse, the user must again attach the cover to the neck, an operation requiring the user to use both hands.
The present invention is directed toward a new type of bottle cap which when secured to an open small neck of a plastic bottle of liquid will enable the user to drink from a bottle by squeezing the bottle so that the liquid is ejected outward therefrom. This cap is so constructed that the liquid will not leak out of the bottle even when the bottle is tilted or held vertically as long as the bottle is not squeezed. Hence it is not necessary to remove or re-attach the cap after use.